Problems with the Dreamliner battery

[AlephZero]

It emerged on Wednesday [Jan 30] that ANA, the largest operator of the 787, had problems with the lithium-ion batteries on its Dreamliners before the emergency landing on January 16.

ANA replaced Dreamliner batteries on 10 occasions last year because of faults with this equipment or related components, although the airline and Boeing said safety was not compromised.

... from http://www.ft.com/cms/s/0/79906f2e-6ac8-11e2-9871-00144feab49a.html#axzz2JV7ZNnGX

I'm sticking with my original "best guess": there won't be a quick fix for this.

An interestng choice of words in the FT article: Boeing is "assuming" (not "forecasting"!) no significant financial impact from all this. Elsewhere, I've seen an estimate that a grounding to the end of 2013 would knock about $7bn off their 2013 earnings, plus knock-on effects on canceled orders and other future business.

EDIT: Those 10 battery incidents at ANA were on a fleet of just 17 aircraft

 

[jim hardy]

This is a complete WAG but maybe we are seeing the effects of strong EM fields on the metal foils that are in tight coils inside each cell when operated at high energy combined with high density levels. Looking at the length of the foils from the Dreamliner cells they would seem to have a fairly large inductance. Rapid current changes from loads or from being charged at high variable rates could be causing some sort of voltage or current non-uniformity inside the cells from the magnetic field effects.

Batteries have a ripple current rating, just like capacitors. Manufacturers caution about ripple in the charger output.

Ripple current
Batteries, as DC devices, prefer to have only DC imposed
on them. The charger’s job is to convert AC into DC but
no charger is 100% efficient. Frequently, filters are added
to chargers to remove the AC current from the DC output.
The AC current on the DC is called ripple current. Battery
manufacturers have stated that more than about 5 A rms
of ripple for every 100 Ah of battery capacity can lead to
premature failure due to internal heating. Ripple voltage is
not a concern since it is the heating effect of the ripple current
that damages batteries. The 5% ripple current figure is
a rough estimate and depends also on the ambient temperature.
Ripple current can increase slowly as the electronic
components in the charger age.

http://www.artec-ingenieria.com/pdf/...uide_en_LR.pdf

Clearly, high crest factor waveform has more heating value than sinewave.
And high frequency would shift that load to the foil nearest the terminals for reason you stated.

I once had to tame some loads - we had SCR style inverters modulating 135 volt 1000 AH batteries to the tune of 100 volt spikes. Their currrent draw was not constant, they drew it in huge gulps. We added one microfarad per milliamp across inverter inputs to calm the battery bus.

So what you suggest is possible.
Ripple and its heating can come either from charger or load.
I'd wager the charger is well behaved,
but the loads are a wag for me, too. In fact an Un-Scientific one, USWAG.

 

[Dotini]

http://seattletimes.com/html/businesstechnology/2020275838_boeingoutsourcingxml.html

The latest in a series of Seattle Times aerospace reporter articles into the 787 electrical woes.

As an off-and-on employee of The Boeing Company from 1968 to 2005, in various positions on all commercial airplane programs, I can relate to the sentiments expressed in the article. The Company may indeed be embroiled in something of a fiasco, but I deeply hope and believe it has the ability and time it needs to recover. My pension may depend upon it!

Respectfully submitted,
Steve

 

[nsaspook]

This seems more related to the current problem.

http://seattletimes.com/html/businesstechnology/2020241162_787battery29xml.html?prmid=obinsource

EaglePicher’s key test — proving that a battery explosion is contained within the box — is one such certification test pre-agreed as satisfying the FAA’s conditions.

The company’s website contends that overcharge explosion tests on its battery were repeated successfully multiple times and concludes that “even during this worst-case scenario, the (battery) is able to contain a thermal event.”
...
However, according to a detailed account of the 787’s battery-fire protection system provided by Sinnett, Boeing’s containment plan did not envisage confining the accident entirely inside the battery box.

Sinnett said Boeing had to demonstrate to the FAA that it had multiple redundant safety mechanisms that ruled out the worst-case scenario that EaglePicher’s test simulates: an overcharged battery explosion

 

[nsaspook]

http://www.thestate.com/2013/02/05/2619386/japan-787-probe-finds-thermal.html#.URGs-uDlAW0

The Japan Transportation Safety Board said that CAT scans and other analysis found damage to all eight cells in the battery that overheated on the All Nippon Airways 787 on Jan. 16, which prompted an emergency landing and probes by both U.S. and Japanese aviation safety regulators.

They also found signs of short-circuiting and "thermal runaway," a chemical reaction in which rising temperature causes progressively hotter temperatures. U.S. investigators found similar evidence in the battery that caught fire last month on a Japan Airlines 787 parked in Boston.

http://mainichi.jp/english/english/newsselect/news/20130206p2g00m0dm001000c.html

All eight cells of the battery installed in the ANA plane showed heat-caused damage, Norihiro Goto, chairman of the Japan Transport Safety Board, said at a press conference.

"Cells 3 and 6 were severely damaged and Cells 1, 2, 7 and 8 were swollen or deformed," Goto said.

He also said that the positive electrode of Cell 3 was found to have experienced particularly severe damage, and wiring inside some cells melted.

 

[AlephZero]

The problem is, they are doing the CT scans etc after a lot of secondary damage occurred. The hard part is figuring out what was the primary cause.

To use a different example, this

looks impressive, but was not very relevant to the investigation compared with looking at what actually broke (or half of it, to be pedantic):
http://www.smarteraircharter.com/news/wp-content/uploads/2010/11/qantas-a380-engine-failure-part-300x225.jpg

After painstakingly dissecting a number of batteries, examining associated electronic parts, and analyzing information from flight-data recorders, NTSB experts and their Japanese counterparts haven't been able to pinpoint any specific component, automated subsystem or software application that appears to offer hope of finding answers.

... from http://online.wsj.com/article/SB10001424127887324761004578284392368343774.html

Having apparently got nowhere after a month of ground testing, Boeing have asked the FAA to approve some 787 flight tests to try to diagnose the problem. Flgiht testing to certify a fix is one thing. Flgiht testing to reproduce an on-board fire hazard is something else. I wonder that the FAA will make of the request

 

[nsaspook]

The problem is, they are doing the CT scans etc after a lot of secondary damage occurred. The hard part is figuring out what was the primary cause.

The failure modes in these cases seem almost identical, a chemically driven positive temperature feedback loop that once started seems to be impossible to stop by all present electronic control measures and so far there seems to be little data on the precursors that start it from all the monitoring data on the system. That leads me to believe the problem is related to what Elon Musk describes (large cells in close contact, thermal and/or electromagnetic effects).

"They [Boeing] believe they have this under control, although I think there is a fundamental safety issue with the architecture of a pack with large cells," writes Musk in an email. "It is much harder to maintain an even temperature in a large cell, as the distance from the center of the cell to the edge is much greater, which increases the risk of thermal runaway."

 

[AlephZero]

A (lack of) progress report from the NTSB investigation: http://www.bbc.co.uk/news/business-21373593
I guess somebody in Boeing is saying "ouch", after those comments.

Re the "test flights", The FAA has granted Boeing permisson for one flight to return a 787 from a "paint job" in Texas back to Everett (i.e. not a test flight as such, though there are conditions imposed on monitoring the batteries while in flight).

Other news: the Europoean air safety agency (EASA) has been invited to join the US investigations. And Polish airline LOT, which has a 787 grounded in Chicago, is applying to the FAA via the EASA, for permission to fly it back home (presumably the fuel cost is less than the long term parking charges!)

 

[AlephZero]

FAA approval for 787 test flights: http://www.faa.gov/news/press_releases/news_story.cfm?newsId=14295

 

[Ptero]

The person I consider to have the best investigative performance to date on this issue is Celina Mikolajczak.

Lithium-Ion Batteries Hazard and Use Assessment
Final Report Prepared by:
Celina Mikolajczak, PE
Michael Kahn, PhD
Kevin White, PhD
Richard Thomas Long, PE
Exponent Failure Analysis Associates, Inc.
© July 2011 Fire Protection Research Foundation
http://www.nfpa.org/assets/files/PDF/Research/RFLithiumIonBatteriesHazard.pdf

I will be glad to provide my opinions on what is contained in this rather damning document, but I am most interested in yours. It is clear to me that this technology is not mature enough in manufacture to be allowed in commercial aircraft. The absolute inability to identify point shorts and dendrite growth, or to prevent Li plating on the anode, the concerns with aging increasing liklihood of shorting, the acceptance of flammable electrolyte, the outgassing of flammable gas and the impossibility of extinguishing electrolyte fires with halon, the cascading effects of thermal runaway events and the inadequate "solution" of boxing this ticking timebomb of a battery in a titanium box vented to the slipstream screams not just of engineering incompetence but of another political mandate gone sour. I do not know if that last bit is true, but I do see Steven Chu scrambling for the exit as Airbus reconsiders Li-Ion deployment.

A kludge (or kluge) is a workaround, a quick-and-dirty solution, a clumsy, inelegant, difficult to extend, hard to maintain yet effective and quick solution to a problem, and a rough synonym to the terms "jury rig", "Jugaad" or "jerry rig". -- Wikipedia

Photos of Japan Airlines January 7 incident, battery pack and cell damage
-- Slide #13: NOTE THE SHORTING DAMAGE THROUGH THE TITANIUM CONTAINMENT! The failure of NTSB's mandated kludge may have been the strongest reason to ground the B-787 fleet. (The melting point of titanium is 3000 F.)
NTSB PDF February 7, 2013
http://www.ntsb.gov/investigations/2013/boeing_787/JAL_B-787_2-7-13.pdf

 

[jim hardy]

Thanks Ptero i forwarded that nfpa paper to a friend at Boeing.

Disasters are always a string of small things stacked up, they topple like Dominoes. That was Ernie Gann's premise in "Fate is the Hunter".
I saw same principle at work in nuclear industry.

In my opinion that is a significant domino.

 

[OmCheeto]

What's this? No one has quoted wiki yet?

Groundings

The focus of the review will be on the safety of the lithium-ion batteries made of lithium cobalt oxide (LiCo). The 787 battery contract was signed in 2005,[195] when LiCo batteries were the only type of lithium aerospace battery available, but since then newer and safer[299] types (such as LiFePO), which provide less reaction energy during thermal runaway, have become available.[193][300] FAA approved a 787 battery in 2007 with nine "special conditions".[301][302] A battery approved by FAA (through Mobile Power Solutions) was made by Rose Electronics using Kokam cells;[303] the batteries installed in the 787 are made by Yuasa[191].

bolding mine

Interesting. But I understand how contracts go. Something better comes along, but we've signed a contract to buy the inherently more dangerous battery.

I changed one of the reference links[193 original ref link], as the original was in some incomprehensible language(Norsk I think). My link points to the following image:

http://www.tu.no/incoming/2013/01/16/1200013182.jpg/ALTERNATES/w620f/1200013182.jpg

hmmm... What was the name of that guy who was so enthralled with LiFePO batteries, that he lost a small fortune investing in a company that made them? What was his name?



----------------------------
Ok to delete, as I am aware that I'm being a, "told you so", kind of smart***

 

[AlephZero]

That last page of the NFPA paper says it is a literature survey about transportation and storage of Li batteries, not about their actual use.

This may be more relevant in showing how faults develop can during use - e.g Fig 5 showing that heat release was delayed for 20 hours after the simulated fault was created.
http://www.evdl.org/docs/li_fault_detection.pdf

If something "goes bang" when you poke it with a sharp stick, there's a fair chance you will speculate there could be a cause and effect mechanism. If it goes bang a day later, for no apparent reason, that's not so easy to understand.

 

[OmCheeto]

That last page of the NFPA paper says it is a literature survey about transportation and storage of Li batteries, not about their actual use.

This may be more relevant in showing how faults develop can during use - e.g Fig 5 showing that heat release was delayed for 20 hours after the simulated fault was created.
http://www.evdl.org/docs/li_fault_detection.pdf

If something "goes bang" when you poke it with a sharp stick, there's a fair chance you will speculate there could be a cause and effect mechanism. If it goes bang a day later, for no apparent reason, that's not so easy to understand.

TLDR. But yes, bang, is not a pleasant sound.

Dec 8, 2011
General Motors Co. (GM), maker of the Chevrolet Volt plug-in hybrid that is the subject of a federal safety probe, is moving to a less volatile battery chemistry for its Chevy Spark electric car going on sale in 2013.
GM is using phosphate-based lithium ion batteries from Waltham, Massachusetts-based A123 Systems Inc. (AONE) that are less likely to burn than other lithium chemistry, including that used in the Volt model introduced last year, said battery experts and suppliers.

Not that their manganese based LIOH battery was that bad. Didn't that Volt catch fire 2 weeks after it had been crash tested?

 

[AlephZero]

Not that their manganese based LIOH battery was that bad. Didn't that Volt catch fire 2 weeks after it had been crash tested?

At which point, one of my engineering mentors would repeat his favorite "development engineering is hard" parable:

Ug the caveman set off to the woods to pick some nuts and berries, but found the path blocked by a large dinosaur, asleep in the sun.

Shouting at the dinosaur had no effect, so Ug went back to his cave, found a sharp stick, and poked the dinosaur in the posterior.

Nothing happened for a couple of hours. Then, the dinosaur got up, took two steps backwards, and sat down on top of Ug, crushing him to death.

Now, the moral of this story is this: the dinosaur did not attack Ug because of the poke from the sharp stick. It was actually responding to a tap on the nose that somebody had given it three weeks earlier.

 

[Ptero]

"Didn't that Volt catch fire 2 weeks after it had been crash tested?"

In this instance, the battery pack had sustained damage and the battery coolant had drained out. The fire occurred, I think, as you state, two weeks later and was blamed by all investigators on a mechanically-damaged cell that initiated the thermal runaway, likely due to a combination of physical damage and a lack of coolant. GM subsequently retrofitted the battery armor on the Volt, beefing it up, and the US DOT accepted this as an effective fix and canceled the investigation. Personally, I do not consider this anything but a kludge based in inadequate investigation. But this was the accident where GM and the NHTSA learned that these battery packs could not be left to sit idle after an accident like their conventional kin, so I am inclined to cut them some slack as a giant and ponderous organization, despite the fact that they failed to listen to some of their more knowledgeable people. However, I am also not satisfied that the entire truth has been told - because of politics - yet there have been no more fires, and no deaths or injuries that I know of, so perhaps I am being too skeptical in regard to magnesium-type Li-Ion, regardless of the fact that it, too, contains flammable electrolyte. Gasoline, diesel, ethanol, propane, natural gas and hydrogen, after all, are also flammable and can ignite in accidents. But spontaneous ignition and thermal runaway, as has occurred in smaller consumer cells and in aviation cargo, or ignition during charging or discharging, or most dramatically with the thermal runaways of Cobalt Li-Ion that resulted in the B-787 fleet grounding, should not be acceptable, imo. Cobalt Li-Ion remains a unique and frightening story. There are serious and unresolved physics problems here - perhaps even fundamental physics barriers that cannot be overcome and extend across the gamut of Li-Ion (this is my personal belief - what do you think?). I do not understand why Cobalt Li-Ion was not entirely abandoned by the aviation industry when the currently insurmountable problems came to light, unless politics played a role. In commercial transport history, it has become de rigueur that virtually all latent design threats to aircraft operations have been immediately addressed and resolved. The implementation of design features with known dangerous faults is unusual in the extreme. That said, I remain suspicious of undetectable dendrite formation in all (flammable electrolyte) Li-Ion battery types so I am keeping a close eye on pure EV as well as hybrid batteries as they age.

 

[jim hardy]

"...There are serious and unresolved physics problems here - perhaps even fundamental physics barriers that cannot be overcome and extend across the gamut of Li-Ion (this is my personal belief - what do you think?)...

I think using big Li-Co batteries is like playing with dynamite.

That said, mea culpa - when i was in college early 1960's every small town hardware store carried dynamite. It was easier to buy dynamite than firecrackers. On a dull Sunday afternoon we boys not infrequently went out to the local rock quarry where we learned to move boulders and uproot trees.
We thought nothing of driving around with a half dozen sticks of the stuff under our car seat.

But dynamite has a fairly high activation energy - you can even hold a match to it and it just fizzles a bit. Unlike those Li-Co batteries, which need only be modestly heated or modestly overcharged to go pyrotechnic on you.

I think i said it earlier - i won't sit in a car seat with one of those batteries underneath my butt. Their low activation energy is a weak latch on a tiger cage.

And that's what i think.

I'm sorry i can't be more scientific about it.

old jim

 

[jim hardy]

I do not know how word 'batteries' in previous post became a link. I tried to edit it out, something not in my control gave it that vigilink attribute.

Odd - it's only a link when i am not logged in.
old jim

"never trust a computer with anything important."

 

[Ptero]

Talked to a pilot who flies for a carrier that had a bunch of B-787s grounded. He said several flight crews had reported overheating battery packs in flight. We may have been very lucky that we didn't lose one over the Pacific.

I haven't heard that anywhere else, btw.

 

[jim hardy]

There's been some trouble. Probably one would have to play golf or go fishing with pilots and airplane mechanics to get the real story .

http://www.aviationweek.com/Article.aspx?id=/article-xml/awx_01_30_2013_p0-542761.xml&p=1

Japan’s two biggest airlines replaced lithium-ion batteries on their Boeing Co 787 Dreamliners in the months before separate incidents led to the technologically advanced aircraft being grounded worldwide due to battery problems.

Comments from both All Nippon Airways, the new Boeing jetliner’s biggest customer to date, and Japan Airlines Co Ltd point to reliability issues with the batteries long before a battery caught fire on a JAL 787 at Boston’s airport and a second battery was badly charred and melted on an ANA domestic flight that was forced into an emergency landing.

ANA said it changed 10 batteries on its 787s last year, but did not inform accident investigators in the United States because the incidents, including five batteries that had unusually low charges, did not compromise the plane’s safety, spokesman Ryosei Nomura said on Wednesday.

JAL also replaced batteries on the 787 “on a few occasions”, said spokeswoman Sze Hunn Yap, declining to be more specific on when units were replaced or whether these were reported to authorities.

ANA did, however, inform Boeing of the faults that began in May, and returned the batteries to their manufacturer, GS Yuasa Corp. ...

 

[AlephZero]

Probably one would have to play golf or go fishing with pilots and airplane mechanics to get the real story.

It's all shared information between the people who can actually make some use of it. Given the amount of air traffic world wide, you shouldn't be too surprised that there are "incidents" somewhere every day of the week, but most of them are no more "news" than the fact that one of your car tires got a puncture and had to be fixed - unless the tire blew and the car ends up upside down in a ditch, of course, which might make it into a "news story". And then some news reporter with a PhD in basket weaving discovers there are a million car tire puctures every year in the USA - shock horror, panic, "car tires are unsafe", etc, etc ...

FWIW we once had quite an argument with the FAA which started from "what's going on here - we AREN'T getting any reports of a particular type of failure from your engines. What are you hiding?", The answer was "nothing", but it took a while to convince them that our desgins were sufficiently different from the competition that they really never did fail that way.

(Note for pedants: I've no idea whether "a million" is the right number or not).

 

[jim hardy]

I didnt mean to suggest a surreptitious coverup or conspiracy.. Sorry.

More along the line firsthand observations are always the best.

Information in a corporation flows much like water in a stream, and any cowboy will tell you : "Always drink upstream of the herd".

old jim

 

[AlephZero]

I didn't think you were suggesting any conspiracy. But the information doesn't just go to the airilne or the plane maker. There are committees and safety boards run by organizations like the FAA and NTSB that have representatives from all the major players, and they get to see data across the whole industry, not just for their own products.

These can end up like Longfellow's poen - "Though the mills of God grind slowly, yet they grind exceeding small". For example a committee set up to investigate this http://en.wikipedia.org/wiki/United_Airlines_Flight_232 back in 1989 is still grinding away at improving inspection methods. One reason it's a slow process is the small amount of data to analyse - it gets about one new "data point" (i.e. somebody detects a potential problem at the manufacturinig stage) per year, and of course some of those turn out to be false positives.

But you won't find that level of information in the public domain, unless somebody leaks it.

 

[AlephZero]

Polish airline LOT announces plans to reschedule summer services, keeping its 787s grounded until October. http://seattletimes.com/html/businesstechnology/2020353578_apeupolanddreamliner.html

Airbus rules out Li batteries on the A350. http://www.bbc.co.uk/news/business-21477126

 

[nsaspook]

Wow, that is really bad news for Boeing if they can't completely nail this problem down to a fixable root cause. I sure hope Boeing has a 'Plan B' that won't take a year of downtime to qualify a new electrical sub-system.

 

[Dotini]

Wow, that is really bad news for Boeing if they can't completely nail this problem down to a fixable root cause. I sure hope Boeing has a 'Plan B' that won't take a year of downtime to qualify a new electrical sub-system.

Boeing management is currently feuding with its engineers. Perhaps a lengthy strike could allow force majeure to be invoked over the delivery schedule and any late delivery penalties.

We know the NTSB and FAA are looking not only into the specific battery woes, but also the design, manufacturing, and underlying certification processes are all up for review. In my humble opinion, all this will take roughly 18-24 months to be resolved.

Since industry analysts are well aware of these issues, it's remarkable how well the price of Boeing stock is holding up.

Respectfully submitted,
Steve

 

[nsaspook]

http://seattletimes.com/html/businesstechnology/2020373450_boeing787xml.html?syndication=rss

The initial redesign includes a fireproof battery box, made of titanium or steel, several sources said. That will seal the cells, keeping moisture out and flames in.

It also includes a venting system that will directly evacuate to the outside any vapor and liquid flowing from the battery.

In the two recent battery overheating incidents, flammable liquid and vapor sprayed out of the battery and across the electronics bay where the battery sits, before reaching an outflow valve.

Longer term, the battery box will be enlarged to provide more separation between the battery’s eight cells, several sources said.

That will help ensure that overheating of one cell doesn’t spread to others — a so-called “thermal runaway” that occurred in both recent incidents.

The battery control system will have sensors to monitor the temperature and voltage of each individual cell rather than the battery as a whole, one source said.

And the same source said engineers are also working on using an inert gas such as halon or nitrogen to expel the oxygen generated when a battery overheats.

 

[OmCheeto]

... and any cowboy will tell you : "Always drink upstream of the herd".

old jim

So how much is this fiasco going to cost all of the parties involved?

And all because of an insignificant, pitiful battery.

This strikes me as pathetic beyond words.

 

[Dotini]

We will know a little bit more by this evening's late news; but a "no" vote and strike authorization does not mean that a walkout is imminent. IF Boeing management doesn't agree to return to the bargaining table by the end of February then something will happen after the 1st week of March. A strike is a get-out-of-delivery-delay-jail free card, BUT I'm not sure that a strike trumps an FAA grounding order.

http://seattletimes.com/html/businesstechnology/2020373450_boeing787xml.html
Boeing has short and medium term plans. Real pain will ensue beyond 9 months.

Meanwhile, back in Everett, 787s are stacking up at the rate of 4 per month and 1 per month in South Carolina.

The original 787 Li-ion battery was certified on the basis that there would only be one "smoke event" per 10 million hours of operation. The 50 787s delivered only have about 50K hours of operation as of January 16, 2013, and have experienced 2 "smoke events".

Not root cause yet but little buggers called dendrites are suspect: http://seattletimes.com/html/businesstechnology/2020342832_787probexml.html

Respectfully,
Steve

 

[AlephZero]

Boeing has short and medium term plans.

The short term plan seems to be "well, we haven't any idea what caused the problem, but hey, let's put the battery in a metal box with a pipe venting overboard to let the smoke out".

That must be a good plan. It's taken "hundreds" of Boeing engineers working "round the clock" to come up with it, according to their press releases.

Even that will take 3 months to certify and retrofit, assuming the FAA are prepared to sign it off. But I can't see the FAA signing anything off until the NTSB have issued a formal investigation report. The only promise date for that is "maybe we can issue a preliminary report by the end of February," but that will only be a record of the facts, not an analysis of the actual problem.

I'm inclined to believe LOT airline's time estimates (October at the earliest for a fix). They don't have anything to lose by being honest.

 

[jim hardy]

http://seattletimes.com/html/businesstechnology/2020373450_boeing787xml.html?syndication=rss
"...The battery control system will have sensors to monitor the temperature and voltage of each individual cell rather than the battery as a whole,..."

What ? One sensor?
As sensitive as these things are to temperature,
IMHO it's very bad judgement to accept the time lag for temperature to transit beween an overheating individual cell and a single sensor that's monitoring the whole battery.
Somebody should have kaboshed that.
Those sensors need to be in intimate contact with their respective cells. Inside them if possible.

If that's what really happened, it is a symptom of too much delegation of design responsibility . And inadequate review.

But it's hard to believe.
So I'll wait on more info about the monitoring & control system architecture.

 

[nsaspook]

I think the FAA and the NTSB believes Boeing played them for fools with the battery special conditions and will force a compete redesign with a different battery type before the plane will fly again. Just containing the fire is not really a option when you need the battery to fly the plane safely.

http://www.evworld.com/focus.cfm?cid=15

The FAA is on the hot seat. Five years ago, they accepted Boeing’s arguments and granted permission to use lithium-ion batteries on the Dreamliner, “if potential fire is contained and fumes vented”. They now have a dilemma – hurting an important domestic industry by doing their job, or becoming discredited if another problem occurs.

 

[OmCheeto]

hmmmm

After offering to help Boeing with its lithium-ion battery problems, Elon Musk is somewhat raising the stakes. Musk, who heads both Tesla Motors and space exploration company SpaceX, has now called the batteries in the Boeing 787 "inherently unsafe" in an e-mail to trade publication Flightglobal.

ref

I've often whined about them using AA sized cells in electric cars. I just found out why they do that, on purpose:

For example, with seven thousand 18650 cells the surface area is roughly 27 square meters. If there were an imaginary set of 20 much larger cube-shaped cells that enclosed the same volume, the surface area would be only 3.5 square meters, more than seven times smaller. Surface area is essential to cooling batteries since the surface is where heat is removed; more is better. Also, because of their small size, each cell is able to quickly redistribute heat within and shed heat to the ambient environment making it essentially isothermal. This cooling architecture avoids “hot spots” which can lead to failures in large battery modules.

ref

I guess it made me crazy imagining trying to connect 7000 cells, or trying to locate one bad cell out of 7000.

 

[Ptero]

Those sensors need to be in intimate contact with their respective cells. Inside them if possible.

That won't work. At least, it will not warn of a problem until the battery is in runaway mode. Why? Because the shorts start at points measured in sub-cubic mm volume. Sure, the sensor might pick up a rising temp indication, but in preventing runaway thermal episodes, you are depending on luck, not engineering.

Amazingly, Boeing, in full recognition of this fact and desparate to get the Dreamliner fleet flying again, proposed to the FAA a new containment box with stainless steel walls nearly one-half an inch thick with a tube venting super-heated gas (plasma) outside the plane at locations at the cockpit and near the trailing edge of the wings. I read this in the Seattle paper, and the reporter speculated that this was not really a good idea because the battery could possibly vent flames during fueling.

And when are the likely times for a runaway condition? On the tarmac during fast charging. I suspect this is exactly what happened to the JAL B-787. But that is not the most serious example the FAA has to deal with. The B-787 that landed with the battery box on fire in Japan came close to erupting into flames in the cockpit IN THE AIR. This could have brought down the plane, killing everyone on board.

I am perplexed at Boeing's response. Obviously, at this juncture, the Li-Cobalt batteries have to be replaced with some other safer type. All safer types require greater volume to produce an equivalent output. The space engineered and built for the box is not large enough so a nightmare retrofit will be necessary. This is a solvable problem but Boeing is in a serious pickle here, on one hand losing millions per day and on the other, having originally provided to the FAA the data and formal assurances on the Li-Co batteries. Not only are they eating crow and losing money, but they have embarrassed the FAA and likely also pissed them off, so a quick return to the skies for the Dreamliner is out of the question in the absence of political corruption (which is not unheard of) or a jiggered peer review (probably harder to pull off).

What is wrong with Boeing? I keep asking myself this. The Li-Co problem was well known. There is no excuse. Has Boeing done something to make their engineers less capable, as NASA did on the loss of a billion-dollar Mars probe when an engineer confused imperial with metric measurement? Was it brought about, perhaps, by government policy, such as hiring mandates? The Boeing incident is even more peculiar because many engineers were involved in this decision. It was not just one who made the mistake, as in the NASA case. I don't know how badly this will hurt Boeing. It will be a deep wound. The only thing I'm certain of is that we taxpayers will end up paying for it in some future military contract.

 

[Ptero]

Digging, I found this. Not sure what to make of it. For now, a coincidence.
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Updated Boeing Statement on 787 Dreamliner ZA002 Incident

EVERETT, Wash., Nov. 11, 2010 /PRNewswire/ -- Boeing continues to investigate Monday's incident on ZA002. We have determined that a failure in the P100 panel led to a fire involving an insulation blanket. The insulation self-extinguished once the fault in the P100 panel cleared. The P100 panel on ZA002 has been removed and a replacement unit is being shipped to Laredo. The insulation material near the unit also has been removed.

Damage to the ZA002 P100 panel is significant. Initial inspections, however, do not show extensive damage to the surrounding structure or other systems. We have not completed our inspections of that area of the airplane.

The P100 panel is one of several power panels in the aft electronics bay. It receives power from the left engine and distributes it to an array of systems. In the event of a failure of the P100 panel, backup power sources – including power from the right engine, the Ram Air Turbine, the auxiliary power unit or the battery – are designed to automatically engage to ensure that those systems needed for continued safe operation of the airplane are powered. The backup systems engaged during the incident and the crew retained positive control of the airplane at all times and had the information it needed to perform a safe landing.

Molten metal has been observed near the P100 panel, which is not unexpected in the presence of high heat. The presence of this material does not reveal anything meaningful to the investigation.

Inspection of the surrounding area will take several days and is ongoing. It is too early to determine if there is significant damage to any structure or adjacent systems.

As part of our investigation, we will conduct a detailed inspection of the panel and insulation material to determine if they enhance our understanding of the incident.

We continue to evaluate data to understand this incident. At the same time, we are working through a repair plan. In addition, we are determining the appropriate steps required to return the rest of the flight test fleet to flying status.

Boeing will continue to provide updates as new understanding is gained.

Contact:

Lori Gunter
787 Communications
+1 206-931-5919

SOURCE Boeing
http://boeing.mediaroom.com/index.php?s=43&item=1515